• The Korean Journal of Pharmacology
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• v.29 no.2
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• pp.225-235
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• 1993

Pituitary LH release has been known to be regulated by the hypothalamic gonadotropin releasing hormone (GnRH) and the gonadal steroid hormones. In addition, neurotransmitters and neuropeptides are actively involved in the control of LH secretion. The alteration in LH release might reflect changes in biosynthesis and/or posttranslational processing of LH. However, little is known about the mechanism by which biosynthesis of LH subunits is regulated, especially at the level of transcription. In order to investigate if ovarian steroid hormones regulate the LH subunit gene expression, ${\alpha}\;and\;LH{\beta}$ steady state mRNA levels were determined in anterior pituitaries of ovariectomized rats. Serum LH concentrations and pituitary LH concentrations were increased markedly with time after ovariectomy. ${\alpha}\;and\;LH{\beta}$ subunit mRNA levels after ovariectomy were increased in a parallel manner with serum LH concentrations and pituitary LH contents, the rise in $LH{\beta}$ subunit mRNA levels being more prominent than the rise in ${\alpha}\;subunit$ mRNA. ${\alpha}\;and\;LH{\beta}$ subunit mRNA levels in ovariectomized rats were negatively regulated by the continuous treatment of ovarian steriod hormones for $1{\sim}4\;days$ and $LH{\beta}\;subunit$ mRNA seemed to be more sensitive to negative feedback of estradiol than progesterone. Treatment of estrogen antagonist, LY117018 or progesterone antagonist, RU486 significantly restroed LH subunit mRNA levels as well as LH release which were suppressed by estradiol or progesterone treatment. These results suggest that ovarian steroids negatively regulate the LH synthesis at the pretranslational level by modulating the steady state levels of ${\alpha}\;and\;LH{\beta}\;subunit$ mRNA and $LH{\beta}\;subunit$ mRNA seemed to be more sensitive to negative feedback action of estradiol than progesterone.

• Radiation Oncology Journal
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• v.21 no.4
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• pp.306-314
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• 2003

Purpose : In our Previous study, we have shown the main cel1 death pattern Induced by irradiation or protein tyrosine kinase (PTK) inhibitors in K562 human myeiogenous leukemic cell line. Death of the cells treated with irradiation alone was characterized by mitotic catastrophe and typical radiation-induced apoptosis was accelerated by herblmycin A (HMA). Both types of cell death were inhibited by genistein. In this study, we investigated the effects of HMA and genistein on cell cycle regulation and its correlation with the alterations of radiation-induced cell death. Materials and Methods: K562 cells In exponential growth phase were used for this study. The cells were Irradiated with 10 Gy using 6 MeV Linac (200-300 cGy/min). Immediately after irradiation, cells were treated with 250 nM of HMA or 25 $\mu$N of genistein. The distributions of cell cycle, the expressions of cell cycle-related protein, the activities of cyclin-dependent kinase, and the yield of senescence and differentiation were analyzed. Results: X-irradiated cells were arrested In the G2 phase of the cell cycle but unlike the p53-positive cells, they were not able to sustain the cell cycle arrest. An accumulation of cells in G2 phase of first ceil-cycle post-treatment and an increase of cyclin Bl were correlated with spontaneous, premature, chromosome condensation and mitotic catastrophe. HMA induced rapid G2 checkpoint abrogation and concomitant p53-independent Gl accumulation. HMA-induced cell cycle modifications correlated with the increase of CDK2 kinase activity, the decrease of the expressions of cyclins I and A and of CDK2 kinase activity, and the enhancement of radiation-induced apoptosis. Genistein maintained cells that were arrested in the G2-phase, decreased the expressions of cyclin Bl and cdc25c and cdc25C kinase activity, increased the expression of pl6, and sustained senescence and megakaryocytic differentiation. Conclusion: The effects of HMA and genistein on the radiation-induced cell death of KS62 cells were closely related to the cell cycle regulatory activities. In this study, we present a unique and reproducible model in which for investigating the mechanisms of various, radiation-induced, cancer cell death patterns. Further evaluation by using this model will provide a potent target for a new strategy of radiotherapy.

• Korean Journal of Microbiology
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• v.43 no.4
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• pp.325-330
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• 2007

RNase E is an essential Escherichia coli endoribonuclease that plays a major role in the decay and processing of a large fraction of RNAs in the cell and expression of N-terminal domain consisted of 1-498 amino acids (N-Rne) is sufficient to support normal cellular growth. By utilizing these properties of RNase E, we developed a genetic system to screen for amino acid substitutions in the catalytic domain of the protein (N-Rne) that lead to various phenotypes. Using this system, we identified three kinds of mutants. A mutant N-Rne containing amino acid substitution in the S1 domain (I6T) of the protein was not able to support survival of E. coli cells, and another mutant N-Rne with amino acid substitution at the position 488 (R488C) in the small domain enabled N-Rne to have an elevated ribonucleolytic activity, while amino acid substitution in the DNase I domain (N305D) only enabled N-Rne to support survival of E. roli cells when the mutant N-Rne was over-expressed. Analysis of copy number of ColEl-type plasmid revealed that effects of amino acid substitution on the ability of N-Rne to support cellular growth stemmed from their differential effects on the ribonucleolytic activity of N-Rne in the cell. These results imply that the genetic system developed in this study can be used to isolate mutant RNase E with various phenotypes, which would help to unveil a functional role of each subdomain of the protein in the regulation of RNA stability in E. coli.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.3
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• pp.324-330
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• 2015

In this study, the anti-diabetic activity of a cold water extract of Korean mistletoe (KME) was investigated in C57BL/6J Lep ob (ob/ob) mice. Oral administration of KME (50 or 100 mg/kg/d) significantly inhibited the level of blood glucose of ob/ob mice after 5 days from the beginning of KME treatment. And the anti-diabetic effect of KME was stabilized 10 days after oral administration, showing a substantial reduction of blood glucose levels by more than 20% as compared with control mice. The results of oral glucose tolerance test (OGTT) revealed that oral administration of KME gave rise to a remarkable improvement in overall glucose response. Oral administration of KME in ob/ob diabetic mice also significantly reduced blood total cholesterol (TCHO) and triglyceride (TG) levels compared with the diabetic control mice. Moreover, in an in vitro experiment using C2C12 myotubes, treatment of KME prominently increased glucose uptake. Interestingly, KME significantly increased the expression of peroxisome proliferator-activated receptor gamma coactivator 1-${\alpha}$ ($PGC-1{\alpha}$), a head regulator of mitochondrial biogenesis and oxidative metabolism, and $PGC-1{\alpha}$-associated genes such as glucose transporter type 4 (GLUT4), estrogen-related receptor-${\alpha}$ ($ERR-{\alpha}$), nuclear respiratory factor-1 (NRF-1), and mitochondrial transcription factor A (TmfA) in C2C12 cells. These results suggest that KME has potential as a novel therapeutic agent for diabetes, and its anti-diabetic activity may be related to the regulation of mitochondrial biogenesis.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.6 no.1
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• pp.81-97
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• 2000

Objectives: This experimental study was carried out to evaluate the effects of aqueous and methanol extracts of Hedyotis diffusa which has long been used for cancer treatment in oriental medicines on the induction of apoptotic cell death in human lymphoid leukemia cell line, HL-60. Methods: Cells were treated with various concentrations (200 to $0.4{\mu}g$) and periods (6 to 30 hr) of $H_2O$ and methanol extracts of Hedyotis diffusa. Then, cells were tested for viability by MTT assay. Cells wrere treated with $200{\mu}g/ml$ of methanol extract fork various periods. Genomic DNA was isolated, separated, on 1.5% agarose gels, stained with ethidium bromide and visualized under UV light. Cells were treated with $200{\mu}g/ml$ of each extract for 16 hr. Then, cells were treated with Hoechst dye 33342 and observed by fluorescence microscopy. Cells were treated with various doses of each for 12 hr and $100{\mu}g/ml$ of methanol extract for various periods. Lysate from the cells used to measure the activity of Caspase-1 and-3 proteases by using fluorogenic peptide substrates including acetyl-YVAD-AMC and acetyl-DEVD-AMC, respectively. Cells were treated with $200{\mu}g/ml$ of each extract for various periods. Cell lysates were immunoprecipated with anti-JNKl antibodies. The immune complex was reacted with $32^p-ATP$ and c-Jun as a substrate. The phosphotransferase activity of JNKI was measured by using PhosphoImage analyzer (Fuji Co., Japan). Nuclear extracts were isolated and incubated with oligonucleotide probe of $NF-{\kappa}B$. Transcriptional activation of ${\kappa}B$ was measured by using EMSA and visualized by PhosphoImage analyzer (Fuji Co, Japan). Cell lysates were prepared and analyzed by Western blotting with anti-Bc12 antibodies and anti-Bax antibodies. Cells were pretreated with various doses of methanol extract for 2 hr. Then, the extract was removed by centrifugation. Cells were resuspended with RPMI-1640 media containing 0.3% agarose, 10% FBS, overlayred onto bottom layer agarose and incubated at $CO_2$ incubator for 6 days. The number of colony was counted under light microscopy ($\time100$). Results: The death of HL-60 cells was markedly induced by the addition of methanol extract of Hedyotis diffusa in a dose and time-dependent manners. The apoptotic characteristic ladder pattern of DNA strand break was observed in death of HL-60 cells. In addition, it was shown nucleus chromatin condensation and fragmentation under Hoechst staining. Therefore, Hedyotis diffusa extract-induced death of HL-60 cells is mediated by apoptotic signaling processes. The activity of Caspase 3-like proteases remained in a basal level in HL-60 cells treated with aqueous extract of Hedyotis diffusa. However, it was markedly increased in HL-60 cells treated with methanol extract of Hedyotis diffusa. In addition, the phosphotransferase activity of JNKl was increased in HL-60 cells treated with methanol extract of Hedyotis diffusa. Furthermore, the activation of transcriptional activator, $NF-{\kappa}B$ was markedly induced by methanol extract of Hedyotis diffusa. Anti-apoptotic Bc12 was cleaved into 23Kda fragment by treatment of methanol extract of Hedyotis diffusa. However, expression of proapoptotic Bax protein was increased by treatment of methanol extract of Hedyotis diffusa in a time-dependent manner. Furthermore, methanol extract markedly inhibited the colony forming efficiency of HL-60 cells in semisolid agar culture. Conclusions: Above results suggest that methanol extract of Hedyotis diffusa induces the apoptotic death of human leukemic HL-60 cells via activations of Caspase-3 proteases, JNKI, transcriptional activator $NF-{\kappa}B$, In addition, our results also suggest that methanol extract of Hedyotis diffusa reduces the malignant potential of HL-60 cells via down regulation of colony forming effciency through cleavage of Bc12 as well as induction of Bax.

• Journal of Life Science
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• v.28 no.1
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• pp.17-25
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• 2018

In this study, we examined the efficacy of the immune regulation of ${\beta}$-1,3/1,6-glucan and Lactobacillus plantarum LM1004 on atopic dermatitis models. The oral administration of ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 on mice significantly decreased the amount of scratching, leakage to evans blue, and concentrations of serum immunoglobulin E (IgE) and histamine compared with the atopic dermatitis - induced group. When atopic dermatitis was induced, the transcription factors (GATA-3, retinoic acid-related orphan receptor ${\gamma}$ T [$ROR{\gamma}T$]) and cytokines (interleukin-4 [IL-4], IL-17) of Th2 and Th17 cells were overexpressed at the transcriptional level, and they significantly decreased with oral administration of ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004. In addition, ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 were shown to modulate the immune balance by increasing the expression of Th1 and Treg transcription (T-bet, forkhead box p3 [Foxp3]) and cytokines (interferon-${\gamma}$ [IFN-${\gamma}$], transforming growth factor-${\beta}$ [TGF-${\beta}$]). Galectin-9 and filaggrin were significantly lower in the atopic dermatitis - induced group and significantly higher in the ${\beta}$-1,3/1,6-glucan-treated group. In contrast, thymic stromal lymphopoietin (TSLP) was highest in the atopic dermatitis-induced group, while mice that were orally administered ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 showed similar TSLP levels to the control group. These results indicate that ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 have immunomodulatory effects and atopic dermatitis improvement effects in an animal model of atopic dermatitis. Therefore, it is expected that ${\beta}$-1,3/1,6-glucan and L. plantarum LM1004 can be used as natural materials in the treatment of atopic dermatitis.

• Journal of Life Science
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• v.21 no.8
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• pp.1149-1155
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• 2011

Myostatin (MSTN) belongs to the transforming growth factor-${\beta}$ superfamily or growth and differentiation factor 8 (GDF-8), and functions as a negative regulator of skeletal muscle development and growth. Previous studies in mammals have suggested that myostatin knock-out increased muscle mass and decreased fat content compared to those of the wide type. Recently, several studies on myostatin have beenconducted on the block myostatin signal pathway with myostatin antagonists and the MSTN regulation with RNAi to control myostatin function. This study was performed to analyze growth and muscle alteration of Oncorhychus masou by treatment with recombinant myostatin prodomains derived from fish. We designed myostatin prodomains derived from P. olivaceus (pMALc2x-poMSTNpro) and S. schlegeli (pMALc2x-sMSTNpro) in a pMALc2x expression vector, and then purified the recombinant proteins using affinity chromatography. The purified recombinant proteins were treated in O. masou through an immersion method. Recombinant protein treated groups did not show a significant difference in weight, protein, or lipid composition compared to the control. However, there was a difference in the average number and area for histological analyses in the muscle fiber. At twelve and twenty-two weeks from the initial treatment, there were differences in averagefiber number and area between the 0.05 mg/l treated-group and the control, but the numbers were similar to those of the control during the same time period. At twelve weeks, however, 0.2 mg/l treated-group had an increase in average fiber number and decrease in average fiber area compared to the control. At twenty-two weeks, the pMALc2x-sMSTNpro 0.2 mg/l treated-group was induced and showed a decrease in average fiber number and increase in average fiber area. The results between twelve and twenty-two weeks showed that the fiber numbers had decreased, whereas average fiberarea had increased due to sMSTNpro. It is understood that the sMSTNpro induced only hyperplasia at twelve weeks, after which it induced hypertrophy. Recombinant myostatin prodomains derived from fish may induce hyperplasia and hypertrophy in O. masou depending upon the time that has elapsed.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.8
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• pp.1197-1206
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• 2016

Adipose tissue in the loin muscle area of beef cattle as a marbling factor is directly associated with beef quality. To elucidate whether properties of proteins involved in depot specific adipose tissue were sex-dependent, we analyzed protein expression of intramuscular adipose tissue (IMAT) and omental adipose tissue (OMAT) from Hanwoo cows, steers, and bulls of Korean native beef cattle by liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomic analysis, quantitative polymerase chain reaction (PCR) and western blot analysis. Two different adipose depots (i.e. intramuscular and omental) were collected from cows (n = 7), steers (n = 7), or bulls (n = 7). LC-MS/MS revealed a total of 55 and 35 proteins in IMAT and OMAT, respectively. Of the 55 proteins identified, 44, 40, and 42 proteins were confirmed to be differentially expressed in IMAT of cows, steers, and bulls, respectively. In OMAT of cows, steers, and bulls, 33, 33, and 22 were confirmed to be differentially expressed, respectively. Tropomyosin (TPM) 1, TPM 2, and TPM3 were subjected to verification by quantitative PCR and western blot analysis in IMAT and OMAT of Hanwoo cows, steers, and bulls as key factors closely associated with muscle development. Both mRNA levels and protein levels of TPM1, TPM2, and TPM3 in IMAT were lower in bulls compared to in cows or steers suggesting that they were positively correlated with marbling score and quality grade. Our results may aid the regulation of marbling development and improvement of meat quality grades in beef cattle.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.806-813
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• 2013

Agrimonia pilosa Ledeb. is a medicinal plant with anti-tumor, anti-oxidant, anti-inflammatory and anti-hyperglycemic activities. However, few studies of the anti-diabetic effect of A. pilosa on insulin resistance status have been performed. In the present study, the anti-diabetic effect of A. pilosa water extract (AP) was determined by investigating its ${\alpha}$-glucosidase inhibitory property, glucose utilization, and uptake, as well as insulin resistance mechanism of action in C2C12 skeletal muscle cells. Compared to positive control (acarbose), AP ($10mg/m{\ell}$) showed a similar ${\alpha}$-glucosidase inhibitory capacity. Glucose uptake was significantly increased by $1{\mu}m$ insulin treatment (p<0.05). However, palmitic acid (FFA, 1 mM) induced muscle insulin resistance and glucose uptake dysfunction. On the other hand, AP ($10{\mu}g/m{\ell}$) was capable of reversing the FFA-induced insulin resistance in C2C12 myotubes. Compared to control, AP ($100{\mu}g/m{\ell}$ without insulin) significantly increased the utilization of glucose (p<0.05) in C2Cl2 myotubes cultured in normal glucose (7 mM). AP treatment significantly increased the relative mRNA and protein expression levels of Akt. In particular, the effect of A. pilosa on the insulin signaling system is associated with the up-regulation of Akt genes and glucose uptake in C2Cl2 myotubes. These results suggest that A. pilosa is useful in the prevention of diabetes and the treatment of hyperglycemic disorders.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.2
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• pp.193-202
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• 2010

In vitro activities of Codonopsis lanceolata (CL) 70% ethanol extract and its fractions (hexane, chloroform, ethyl acetate, butanol and water) were examined by total polyphenol content, reducing power, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS), 2,2-diphenyl-$\beta$-picrylhydrazyl (DPPH), and oxygen radical absorbance capacity (ORAC) assays. The ethyl acetate fraction from CL ethanol extract (CLEA) showed the highest total polyphenol content (22.7 mg/g) among five fractions, and also exhibited an excellent reducing power (0.42~1.27 at $250\sim1,000\;{\mu}g/mL$). CLEA at $100\sim400\;{\mu}g/mL$ concentrations had 27.7~70.3% of ABTS radical scavenging activity and the highest DPPH radical scavenging activity (81.6% at $400\;{\mu}g/mL$). CLEA had dominantly higher $ORAC_{{ROO}{\cdot}}$activity compared to other fractions. CLEA and butanol fraction had significantly higher $ORAC_{{OH}{\cdot}}$ activities than 70% ethanol extract, hexane, chloroform and water fractions. The CLEA exhibited the highest antioxidant activity in CL 70% ethanol extract and its fractions. Thus, effect of CLEA treatment on antioxidant gene expression under the oxidative stress conditions by a high fat diet in animal model was studied by microarray and RT-PCR methods. The 31 antioxidant genes were expressed but the genes were not up-regulated at least a two-fold by CLEA treatment. We concluded that CLEA does not have an indirect antioxidant effect but a direct antioxidant effect by up-regulation of antioxidant genes in high fat diet-induced obese mice.